Electro-enhanced solid-phase microextraction method

Abstract

The electro-enhanced solid-phase microextraction (EE-SPME) method involves extraction that is performed with an SPME fiber, preferably made of polydimethylsiloxane (PDMS), in the presence of an applied electric potential for a predetermined period of time. Polar analytes are extracted onto the fiber, which is the stationary phase. The solid-phase microextraction fiber is then inserted into an injection port of a gas chromatograph coupled with a mass spectrometer. The polar analytes are desorbed in the injection port, and are analyzed by GC-MS to detect and quantify the individual components. The method is particularly useful for the detection of trace amounts of plasticizers, such as phthalate esters and bisphenol A, that are known to disrupt the endocrine system of humans and animals above known levels

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to separation techniques, and particularly to an electro-enhanced solid-phase microextraction method that is particularly useful for the detection of endocrine disruptor chemicals (EDCs) in liquid samples, such as seawater and human blood.[0003]2. Description of the Related Art[0004]Solid-phase microextraction (SPME) is a sample preparation technique used both in the laboratory and on-site. Developed in the early 1990s, it is a relatively simple and inexpensive technique in which solvents are not used. SPME involves the use of a fiber coated with an extracting phase, which can be either a liquid (polymer) or a solid (sorbent), which extracts different types of analytes (including both volatile and non-volatile) from different kinds of media, which may be in liquid or gas phase. The quantity of analyte extracted by the fiber is proportional to its concentration in the sample, as long as equi...

AI Technical Summary

Benefits of technology

The electro-enhanced solid-phase microextraction (EE-SPME) method is used to detect endocrine disruptor chemicals (EDCs) in liquid samples, such as seawater and human blood samples. The method involves extraction with aSPME fiber over an extraction time of about 20 minutes with an applied electrical potential of about 32 V. The extracts are then analyzed using gas chromatography and mass spectrometry. The invention provides a faster and more efficient method for detecting EDCs.

Problems solved by technology

Additionally, detection limits can reach parts per trillion (ppt) levels for certain compounds.

These plasticizers easily leach under harsh environmental conditions.

Further, the carcinogenic toxicity of EDCs are well documented, even at very low concentrations, and their mode of action mimics estrogenic activity and may affect the health and reproduction systems of both humans and wildlife.

However, LLE and SPE require relatively large volumes of organic solvents and multi-step extractions.

Thus, these techniques are not suitable for trace level determination of EDCs in water and food samples.

However, the selection of suitable solvents for the extraction of polar analytes, such as PAEs and BPA, is a challenging task in LPME and DLLME.

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